Antenna having flexible feed structure with components

ABSTRACT

Electronic devices may include antenna structures. The antenna structures may form an antenna having first and second feeds at different locations. Transceiver circuitry for transmitting and receiving radio-frequency antenna signals may be mounted on one end of a printed circuit board. Transmission line structures may be used to convey signals between an opposing end of the printed circuit board and the transceiver circuitry. The printed circuit board may be coupled to an antenna feed structure formed from a flexible printed circuit using solder connections. The flexible printed circuit may have a bend and may be screwed to conductive electronic device housing structures using one or more screws at one or more respective antenna feed terminals. Electrical components such as an amplifier circuit and filter circuitry may be mounted on the flexible printed circuit.

This application is a continuation of U.S. patent application Ser. No.13/435,351, filed Mar. 30, 2012. This application claims the benefit ofand claims priority to U.S. patent application Ser. No. 13/435,351,filed Mar. 30, 2012, which is hereby incorporated by reference herein inits entirety.

BACKGROUND

This relates generally to electronic devices, and more particularly, toantenna structures for electronic devices with wireless communicationscircuitry.

Electronic devices such as portable computers and cellular telephonesare often provided with wireless communications capabilities. Forexample, electronic devices may use long-range wireless communicationscircuitry such as cellular telephone circuitry to communicate usingcellular telephone bands. Electronic devices may use short-rangewireless communications circuitry such as wireless local area networkcommunications circuitry to handle communications with nearby equipment.Electronic devices may also be provided with satellite navigation systemreceivers and other wireless circuitry.

To satisfy consumer demand for small form factor wireless devices,manufacturers are continually striving to implement wirelesscommunications circuitry such as antenna components using compactstructures. At the same time, it may be desirable to include conductivestructures in an electronic device such as metal device housingcomponents. Because conductive components can affect radio-frequencyperformance, care must be taken when incorporating antennas into anelectronic device that includes conductive structures. Moreover, caremust be taken to ensure that the antennas and wireless circuitry in adevice are able to exhibit satisfactory performance over a range ofoperating frequencies.

It would therefore be desirable to be able to provide improved antennastructures for wireless electronic devices.

SUMMARY

Electronic devices may include antenna structures. The antennastructures may be formed from antenna resonating element and groundstructures. The antenna resonating element structures may be formed fromconductive portions of an electronic device housing such as peripheralconductive housing structures. The ground structures may include housingstructures, printed circuit board traces, and other conductivestructures. The ground structures associated with an antenna may beseparated from peripheral conductive housing structures or other antennaresonating element structures by a gap.

The antenna structures may form an antenna having a single feed orhaving first and second feeds at different locations. Transceivercircuitry for transmitting and receiving radio-frequency antenna signalsmay be mounted on a first end of a printed circuit board. Transmissionline structures may be used to convey signals between an opposing secondend of the printed circuit board and the first end of the printedcircuit board.

The printed circuit board may be coupled to an antenna feed structureformed from a flexible printed circuit using solder connections. Theflexible printed circuit may have a bend. One edge of the flexibleprinted circuit may be coupled to the printed circuit board using thesolder connections or other electrical connections. The other edge ofthe flexible printed circuit may be attached to the vertical innersurface of a peripheral conductive housing structure or other antennaresonating element structure. The flexible printed circuit may, forexample, be screwed to the conductive electronic device housingstructures using one or more screws at one or more antenna feedterminals.

Electrical components such as an amplifier circuit and filter circuitrymay be mounted on the flexible printed circuit.

Further features of the invention, its nature and various advantageswill be more apparent from the accompanying drawings and the followingdetailed description of the preferred embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an illustrative electronic device withwireless communications circuitry in accordance with an embodiment ofthe present invention.

FIG. 2 is a schematic diagram of an illustrative electronic device withwireless communications circuitry in accordance with an embodiment ofthe present invention.

FIG. 3 is a diagram of an illustrative antenna structure in accordancewith an embodiment of the present invention.

FIG. 4 is a diagram of an illustrative electronic device of the typeshown in FIG. 1 showing how structures in the device may form a groundplane and antenna resonating element structures in accordance with anembodiment of the present invention.

FIG. 5 is a diagram showing how device structures of the type shown inFIG. 4 may be used in forming an antenna with multiple feeds inaccordance with an embodiment of the present invention.

FIG. 6 is a diagram of an antenna of the type shown in FIG. 5 withmultiple feeds and associated wireless circuitry such as filters andmatching circuits in accordance with an embodiment of the presentinvention.

FIG. 7 is a cross-sectional side view of a portion of a device of thetype shown in FIG. 4 showing how an antenna feed may be formed using aflexible printed circuit that spans a gap between a printed circuitboard and a peripheral conductive housing structure in accordance withan embodiment of the present invention.

FIG. 8 is a perspective view of conductive housing structures that maybe used in forming a device of the type shown in FIG. 1 in accordancewith an embodiment of the present invention.

FIG. 9 is a top view of an electronic device with antenna structuresthat may use an antenna feed arrangement of the type shown in FIG. 7 inaccordance with an embodiment of the present invention.

FIG. 10 is a perspective view of a portion of a device housing showinghow a device with an antenna structure of the type shown in FIG. 9 maybe provided with an antenna feed arrangement of the type shown in FIG. 7in accordance with an embodiment of the present invention.

FIG. 11 is a top view of an illustrative flexible printed circuit of thetype that may be used in forming an antenna feed structure with a lownoise amplifier and other electrical components in accordance with anembodiment of the present invention.

FIG. 12 is a cross-sectional side view of an electronic device having afeed structure formed from a flexible substrate with attached electricalcomponents such as a low noise amplifier in accordance with anembodiment of the present invention.

DETAILED DESCRIPTION

Electronic devices such as electronic device 10 of FIG. 1 may beprovided with wireless communications circuitry. The wirelesscommunications circuitry may be used to support wireless communicationsin one or more wireless communications bands. The wirelesscommunications circuitry may include one or more antennas.

The antennas can include loop antennas, inverted-F antennas, stripantennas, planar inverted-F antennas, slot antennas, hybrid antennasthat include antenna structures of more than one type, or other suitableantennas. Conductive structures for the antennas may, if desired, beformed from conductive electronic device structures. The conductiveelectronic device structures may include conductive housing structures.The housing structures may include a peripheral conductive structurethat runs around the periphery of an electronic device. The peripheralconductive structure may be formed from a separaterectangular-ring-shaped member or some or all of the peripheralconductive structure may be formed as an integral portion of a rearhousing plate (as examples). The peripheral conductive structure, whichmay sometimes be referred to as a peripheral conductive member orperipheral housing structures, may serve as a bezel for a planarstructure such as a display, may serve as sidewall structures for adevice housing, and/or may form other housing structures. Gaps in theperipheral conductive member may be associated with antennas in device10.

Electronic device 10 may be a portable electronic device or othersuitable electronic device. For example, electronic device 10 may be alaptop computer, a tablet computer, a somewhat smaller device such as awrist-watch device, pendant device, headphone device, earpiece device,or other wearable or miniature device, a cellular telephone, or a mediaplayer. Device 10 may also be a television, a set-top box, a desktopcomputer, a computer monitor into which a computer has been integrated,or other suitable electronic equipment.

Device 10 may include a housing such as housing 12. Housing 12, whichmay sometimes be referred to as a case, may be formed of plastic, glass,ceramics, fiber composites, metal (e.g., stainless steel, aluminum,etc.), other suitable materials, or a combination of these materials. Insome situations, parts of housing 12 may be formed from dielectric orother low-conductivity material. For example, glass structures, plasticstructures, or other dielectric structures may be used to form exteriorand interior portions of housing 12. In other situations, housing 12 orat least some of the structures that make up housing 12 may be formedfrom metal elements.

Device 10 may, if desired, have a display such as display 14. Display 14may, for example, be a touch screen that incorporates capacitive touchelectrodes. Display 14 may include image pixels formed fromlight-emitting diodes (LEDs), organic LEDs (OLEDs), plasma cells,electrowetting pixels, electrophoretic pixels, liquid crystal display(LCD) components, or other suitable image pixel structures. A coverglass layer may cover the surface of display 14. Buttons such as button19 may pass through openings in the cover glass. The cover glass mayalso have other openings such as an opening for speaker port 26.

Housing 12 may include peripheral conductive portions. For example,housing 12 may include peripheral conductive structures such asperipheral conductive member 16. Member 16 may run around the peripheryof device 10 and display 14. Member 16 or portions of member 16 may forman integral part of a planar rear housing structure (e.g., a planar rearhousing wall) and/or separate housing structures. In configurations inwhich device 10 and display 14 have a rectangular shape, member 16 mayhave a rectangular ring shape (as an example). Member 16 or part ofmember 16 may serve as a bezel for display 14 (e.g., a cosmetic trimthat surrounds all four sides of display 14 and/or helps hold display 14to device 10). Member 16 may also, if desired, form sidewall structuresfor device 10 (e.g., by forming a metal band with vertical sidewalls, byforming sidewalls that extend vertically from a planar rear housingmember, etc.).

Member 16 may be formed of a conductive material and may thereforesometimes be referred to as a peripheral conductive member, peripheralconductive structures, or conductive housing structures. Member 16 maybe formed from a metal such as stainless steel, aluminum, or othersuitable materials. One, two, or more than two separate structures maybe used in forming member 16.

It is not necessary for member 16 to have a uniform cross-section. Forexample, the top portion of member 16 may, if desired, have an inwardlyprotruding lip that helps hold display 14 in place. If desired, thebottom portion of member 16 may also have an enlarged lip (e.g., in theplane of the rear surface of device 10). In the example of FIG. 1,member 16 has substantially straight vertical sidewalls. This is merelyillustrative. The sidewalls of member 16 may be curved or may have anyother suitable shape. In some configurations (e.g., when member 16serves as a bezel for display 14), member 16 may run around the lip ofhousing 12 (i.e., member 16 may cover only the edge of housing 12 thatsurrounds display 14 and not the rear edge of housing 12 of thesidewalls of housing 12).

Display 14 may include conductive structures such as an array ofcapacitive electrodes, conductive lines for addressing pixel elements,driver circuits, etc. Housing 12 may include internal structures such asmetal frame members, a planar interior housing member (sometimesreferred to as a midplate) that spans the walls of housing 12 (i.e., oneor more sheet metal structures that form a substantially rectangularmember that is welded or otherwise connected between opposing sides ofmember 16), a planar rear housing wall, printed circuit boards, andother conductive structures. These conductive structures may be locatedin the center of housing 12 under display 14 (as an example).

In regions 22 and 20, openings (gaps) may be formed within theconductive structures of device 10 (e.g., between peripheral conductivemember 16 and opposing conductive structures such as conductive housingstructures, a conductive ground plane associated with a printed circuitboard, a conductive rear housing wall, conductive components such as adisplay, and other conductive electrical components in device 10). Theseopenings may be filled with air, plastic, and other dielectrics.Conductive housing structures and other conductive structures in device10 may serve as a ground plane for the antennas in device 10. Theopenings in regions 20 and 22 may serve as slots in open or closed slotantennas, may serve as a central dielectric region that is surrounded bya conductive path of materials in a loop antenna, may serve as a spacethat separates an antenna resonating element such as a strip antennaresonating element or an inverted-F antenna resonating element from theground plane, or may otherwise serve as part of antenna structuresformed in regions 20 and 22.

In general, device 10 may include any suitable number of antennas (e.g.,one or more, two or more, three or more, four or more, etc.). Theantennas in device 10 may be located at opposing first and second endsof an elongated device housing, along one or more edges of a devicehousing, in the center of a device housing, in other suitable locations,or in one or more of such locations. The arrangement of FIG. 1 is merelyillustrative.

Portions of member 16 may be provided with gap structures. For example,member 16 may be provided with one or more gaps such as gaps 18, asshown in FIG. 1. The gaps may be filled with dielectric such as polymer,ceramic, glass, air, other dielectric materials, or combinations ofthese materials. Gaps 18 may divide peripheral conductive member 16(e.g., the sidewalls of housing 12) into one or more peripheralconductive member segments. There may be, for example, two segments ofmember 16 (e.g., in an arrangement with two gaps), three segments ofmember 16 (e.g., in an arrangement with three gaps), four segments ofmember 16 (e.g., in an arrangement with four gaps, etc.). The segmentsof peripheral conductive member 16 that are formed in this way may formparts of antennas in device 10.

In a typical scenario, device 10 may have upper and lower antennas (asan example). An upper antenna may, for example, be formed at the upperend of device 10 in region 22. A lower antenna may, for example, beformed at the lower end of device 10 in region 20. The antennas may beused separately to cover identical communications bands, overlappingcommunications bands, or separate communications bands. The antennas maybe used to implement an antenna diversity scheme or amultiple-input-multiple-output (MIMO) antenna scheme.

Antennas in device 10 may be used to support any communications bands ofinterest. For example, device 10 may include antenna structures forsupporting local area network communications, voice and data cellulartelephone communications, global positioning system (GPS) communicationsor other satellite navigation system communications, Bluetooth®communications, etc.

A schematic diagram of an illustrative configuration that may be usedfor electronic device 10 is shown in FIG. 2. As shown in FIG. 2,electronic device 10 may include storage and processing circuitry 28.Storage and processing circuitry 28 may include storage such as harddisk drive storage, nonvolatile memory (e.g., flash memory or otherelectrically-programmable-read-only memory configured to form a solidstate drive), volatile memory (e.g., static or dynamicrandom-access-memory), etc. Processing circuitry in storage andprocessing circuitry 28 may be used to control the operation of device10. The processing circuitry may be based on one or moremicroprocessors, microcontrollers, digital signal processors, basebandprocessors, power management units, audio codec chips, applicationspecific integrated circuits, etc.

Storage and processing circuitry 28 may be used to run software ondevice 10, such as internet browsing applications,voice-over-internet-protocol (VOIP) telephone call applications, emailapplications, media playback applications, operating system functions,etc. To support interactions with external equipment, storage andprocessing circuitry 28 may be used in implementing communicationsprotocols. Communications protocols that may be implemented usingstorage and processing circuitry 28 include internet protocols, wirelesslocal area network protocols (e.g., IEEE 802.11 protocols—sometimesreferred to as WiFi®), protocols for other short-range wirelesscommunications links such as the Bluetooth® protocol, cellular telephoneprotocols, etc.

Circuitry 28 may be configured to implement control algorithms thatcontrol the use of antennas in device 10. For example, circuitry 28 mayperform signal quality monitoring operations, sensor monitoringoperations, and other data gathering operations and may, in response tothe gathered data and information on which communications bands are tobe used in device 10, control which antenna structures within device 10are being used to receive and process data and/or may adjust one or moreswitches, tunable elements, or other adjustable circuits in device 10 toadjust antenna performance. As an example, circuitry 28 may controlwhich of two or more antennas is being used to receive incomingradio-frequency signals, may control which of two or more antennas isbeing used to transmit radio-frequency signals, may control the processof routing incoming data streams over two or more antennas in device 10in parallel, may tune an antenna to cover a desired communications band,etc. In performing these control operations, circuitry 28 may open andclose switches, may turn on and off receivers and transmitters, mayadjust impedance matching circuits, may configure switches inradio-frequency circuits that are interposed between radio-frequencytransceiver circuitry and antenna structures (e.g., filtering andswitching circuits used for impedance matching and signal routing), mayadjust switches, tunable circuits, and other adjustable circuit elementsthat are formed as part of an antenna or that are coupled to an antennaor a signal path associated with an antenna, and may otherwise controland adjust the components of device 10.

Input-output circuitry 30 may be used to allow data to be supplied todevice 10 and to allow data to be provided from device 10 to externaldevices. Input-output circuitry 30 may include input-output devices 32.Input-output devices 32 may include touch screens, buttons, joysticks,click wheels, scrolling wheels, touch pads, key pads, keyboards,microphones, speakers, tone generators, vibrators, cameras, sensors,light-emitting diodes and other status indicators, data ports, etc. Auser can control the operation of device 10 by supplying commandsthrough input-output devices 32 and may receive status information andother output from device 10 using the output resources of input-outputdevices 32.

Wireless communications circuitry 34 may include radio-frequency (RF)transceiver circuitry formed from one or more integrated circuits, poweramplifier circuitry, low-noise input amplifiers, passive RF components,one or more antennas, and other circuitry for handling RF wirelesssignals. Wireless signals can also be sent using light (e.g., usinginfrared communications).

Wireless communications circuitry 34 may include satellite navigationsystem receiver circuitry 35 such as Global Positioning System (GPS)receiver circuitry (e.g., for receiving satellite positioning signals at1575 MHz) or satellite navigation system receiver circuitry associatedwith other satellite navigation systems. Transceiver circuitry 36 mayhandle 2.4 GHz and 5 GHz bands for WiFi® (IEEE 802.11) communicationsand may handle the 2.4 GHz Bluetooth® communications band. Circuitry 34may use cellular telephone transceiver circuitry 38 for handlingwireless communications in cellular telephone bands such as bands infrequency ranges of about 700 MHz to about 2200 MHz or bands at higheror lower frequencies. Wireless communications circuitry 34 can includecircuitry for other short-range and long-range wireless links ifdesired. For example, wireless communications circuitry 34 may includewireless circuitry for receiving radio and television signals, pagingcircuits, etc. In WiFi® and Bluetooth® links and other short-rangewireless links, wireless signals are typically used to convey data overtens or hundreds of feet. In cellular telephone links and otherlong-range links, wireless signals are typically used to convey dataover thousands of feet or miles.

Wireless communications circuitry 34 may include one or more antennas40. Antennas 40 may be formed using any suitable antenna types. Forexample, antennas 40 may include antennas with resonating elements thatare formed from loop antenna structure, patch antenna structures,inverted-F antenna structures, closed and open slot antenna structures,planar inverted-F antenna structures, helical antenna structures, stripantennas, monopoles, dipoles, hybrids of these designs, etc. Differenttypes of antennas may be used for different bands and combinations ofbands. For example, one type of antenna may be used in forming a localwireless link antenna and another type of antenna may be used in forminga remote wireless link.

If desired, antennas 40 may include adjustable components so thatantennas 40 can be tuned to cover desired communications bands ofinterest. Each of antennas 40 may have a single antenna feed or may havemultiple antenna feeds. For example, an antenna with multiple feeds mayhave a first antenna feed that is associated with a first set ofcommunications frequencies and a second antenna feed that is associatedwith a second set of communications frequencies. The use of multiplefeeds (and/or adjustable antenna components) may make it possible toreduce antenna size (volume) within device 10 while satisfactorilycovering desired communications bands.

An illustrative configuration for an antenna of the type that may beused in device 10 is shown in FIG. 3. Antenna 40 of FIG. 3 may have oneor more antenna feeds. As shown in FIG. 3, antenna 40 may haveconductive antenna structures such as antenna resonating element 50 andantenna ground 52. The conductive structures that form antennaresonating element 50 and antenna ground 52 may be formed from parts ofconductive housing structures, from parts of electrical devicecomponents in device 10, from printed circuit board traces (e.g.,conductive lines such as conductive paths formed from metal), fromstrips of conductor such as strips of wire and metal foil, or otherconductive materials.

Each antenna feed associated with antenna 40 may, if desired, have adistinct location. As shown in FIG. 3, antenna 40 may have a first feedsuch as feed FA at a first location in antenna 40, a second feed such asfeed FB at a second location in antenna 40, and one or more additionalantenna feeds at potentially different respective locations of antenna40.

Each of the one or more feeds associated with antenna 40 may be coupledto an associated set of conductive signal paths using terminals such aspositive antenna feed terminals (+) and ground antenna feed terminals(−). For example, path 54A may have a positive conductor 58A that iscoupled to a positive antenna feed terminal in feed FA and a groundconductor 56A that is coupled to a ground antenna feed terminal in feedFA, whereas path 54B may have a positive conductor 58B that is coupledto a positive antenna feed terminal in feed FB and a ground conductor56B that is coupled to a ground antenna feed terminal in feed FB. Pathssuch as paths 54A and 54B may be implemented using transmission linestructures such as coaxial cables, microstrip transmission lines (e.g.,microstrip transmission lines on printed circuits), striplinetransmission lines (e.g., stripline transmission lines on printedcircuits), or other transmission lines or signal paths. Circuits such asimpedance matching and filter circuits and other circuitry may beinterposed within paths 54A and 54B.

Paths such as paths 54A and 54B may be used to couple antenna feeds forone or more antennas 40 to radio-frequency transceiver circuitry such asreceiver (transceiver) 35 and transceivers 36 and/or 38 of FIG. 2. Path54A may include one or more transmission line segments and may includepositive conductor 56A and ground conductor 58A. Path 54B may includeone or more transmission line segments and may include positiveconductor 56B and ground conductor 58B. One or more circuits such asfilter circuits, impedance matching circuits, switches, amplifiercircuits, and other circuits may be interposed within paths 54A and 54B.

With one illustrative configuration, a first path such as path 54A maybe coupled between a first radio-frequency transceiver circuit and firstantenna feed FA and a second path such as path 54B may be used to couplea second radio-frequency transceiver circuit to second antenna feed FB.Feeds FA and FB may be used in transmitting and/or receivingradio-frequency antenna signals. The first transceiver may include aradio-frequency receiver and/or a radio-frequency transmitter. Thesecond transceiver may also include a radio-frequency receiver and/or aradio-frequency transmitter.

The first transceiver may, as an example, be a transceiver such as asatellite navigation system receiver and the second transceiver may, asan example, be a transceiver such as a cellular telephone transceiver(having a cellular telephone transmitter and a cellular telephonereceiver). As another example, the first transceiver may have atransmitter and/or a receiver that operate at frequencies associatedwith a first communications band (e.g., a first cellular or wirelesslocal area network band) and the second transceiver may have atransmitter and/or a receiver that operate at frequencies associatedwith a second communications band (e.g., a second cellular or wirelesslocal area network band). Other types of configurations may be used, ifdesired. The transceivers may be implemented using separate integratedcircuits or may be integrated into a common integrated circuit (asexamples). One or more associated additional integrated circuits (e.g.,one or more baseband processor integrated circuits) may be used toprovide the transceiver circuitry with data to be transmitted by antenna40 and may be used to receive and process data that has been received byantenna 40.

Filter circuitry, impedance matching circuitry, switches, amplifiers,and other electrical components may be interposed in paths such as paths54A and 54B. For example, a first filter may be interposed in path 54Abetween feed FA and a first transceiver, so that signals that aretransmitted and/or received using antenna feed FA are filtered by thefirst filter. A second filter may likewise be interposed in path 54B, sothat signals that are transmitted and/or received using antenna feed FBare filtered by the second filter. The filters may be adjustable orfixed. In fixed filter configurations, the transmittance of the filtersas a function of signal frequency is fixed. In adjustable filterconfigurations, adjustable components may be placed in different statesto adjust the transmittance characteristics of the filters.

If desired, fixed and/or adjustable impedance matching circuits (e.g.,circuitry for impedance matching a transmission line to antenna 40 orother wireless circuitry) may be included in paths 54A and 54B (e.g., aspart of filters or as separate circuits). In a multi-feed antenna, thefirst and second filters may be configured so that the antenna feeds inthe antenna may operate satisfactorily, even in a configuration in whichmultiple feeds are coupled to antenna 40 simultaneously.

A top interior view of device 10 in a configuration in which device 10has a peripheral conductive structure such as peripheral conductivehousing member 16 of FIG. 1 with one or more gaps 18 is shown in FIG. 4.As shown in FIG. 4, device 10 may have an antenna ground plane such asantenna ground plane 52. Ground plane 52 may be formed from traces onprinted circuit boards (e.g., rigid printed circuit boards and flexibleprinted circuit boards), from conductive planar support structures inthe interior of device 10, from conductive structures that form exteriorparts of housing 12 (e.g., some or all of a conductive rear housing wallstructure), from conductive structures that are part of one or moreelectrical components in device 10 (e.g., parts of connectors, switches,cameras, speakers, microphones, displays, buttons, etc.), or otherconductive device structures. Gaps such as gaps 82 may be filled withair, plastic, or other dielectric.

One or more segments of peripheral conductive member 16 may serve asantenna resonating elements such as antenna resonating element 50 ofFIG. 3. For example, the uppermost segment of peripheral conductivemember 16 in region 22 may serve as an antenna resonating element for anantenna in device 10. The conductive materials of peripheral conductivemember 16, the conductive materials of ground plane 52, and dielectricopenings (gaps) 82 (and gaps 18) may be used in forming one or moreantennas in device 10 such as an upper antenna in region 22 and a lowerantenna in region 20. Antennas in regions 20 and 22 may each have asingle feed or multiple feeds.

Using a device configuration of the type shown in FIG. 5, a dual-feedantenna for device 10 may be implemented (e.g., a dual-feed inverted-Fantenna). Segment 16′ of the peripheral conductive member (see, e.g.,peripheral conductive structures 16 of FIG. 4) may form antennaresonating element 50. Ground plane 52 may be separated from antennaresonating element 50 by gap 82. Gaps 18 may be formed at either end ofsegment 16′ and may have associated parasitic capacitances. Conductivepath 84 may form a short circuit path between antenna resonating element(i.e., segment 16′) and ground 52. First antenna feed FA and secondantenna feed FB may be located at different locations along the lengthof antenna resonating element 50.

As shown in FIG. 6, it may be desirable to provide each of the feeds ofantenna 40 with filter circuitry and impedance matching circuitry. In aconfiguration of the type shown in FIG. 6, antenna resonating element 50may be formed from a segment of peripheral conductive member 16 (e.g.,segment 16′ of FIG. 5). Antenna ground 52 may be formed from groundplane structures such as ground plane structure 52 of FIG. 5. Antenna 40of FIG. 6 may be, for example, an upper antenna in region 22 of device10 (e.g., an inverted-F antenna). Device 10 may also have additionalantennas such as antenna 40′ (e.g., an antenna formed in lower portion20 of device 10, as shown in FIG. 4).

In the illustrative example of FIG. 6, satellite navigation receiver 35(e.g., a Global Positioning System receiver or a receiver associatedwith another satellite navigation system or other type of transceiver)may serve as a first transceiver for device 10, whereas cellulartelephone transceiver circuitry 38 (e.g., a cellular telephonetransmitter and a cellular telephone receiver or another type oftransceiver) may serve as a second transceiver for device 10. Ifdesired, other types of transceiver circuitry may be used in device 10.The example of FIG. 6 is merely illustrative.

As shown in FIG. 6, receiver 35 may be coupled to antenna 40 at firstantenna feed FA and transceiver 38 may be coupled to antenna 40 atsecond antenna feed FB.

Incoming signals for receiver 35 may be received through band-passfilter 64A, optional impedance matching circuits such as matchingcircuits M1 and M4, and low noise amplifier 86. The signals receivedfrom feed FA may be conveyed through components such as matching filterM1, band-pass filter 64A, matching circuit M4, and low noise amplifier86 using transmission lines paths such as transmission line path 54A.Additional components may be interposed in transmission line path 54A,if desired.

Signals associated with transmit and receive operations for cellulartransceiver circuitry 38 may be handled using notch filter 64B, optionalimpedance matching circuits such as matching circuits M2 and M3, antennaselection switch 88, and circuitry 90. Antenna selection switch 88 mayhave a first state in which antenna 40 is coupled to transceiver 38 anda second state in which antenna 40′ is coupled to transceiver 38 (as anexample). If desired, switch 88 may be a cross-bar switch that coupleseither antenna 40 or antenna 40′ to transceiver 38 while coupling theremaining antenna to another transceiver.

Circuitry 90 may include filters (e.g., duplexers, diplexers, etc.),power amplifier circuitry for amplifying transmitted signals, bandselection switches, and other components. The components used intransmitting and receiving signals with feed FB may be conveyed throughcomponents such as matching filter M2, notch filter 64B, matchingcircuit M3, and circuitry 90 using transmission lines paths such astransmission line path 54B (see, e.g., FIGS. 3 and 9). Additionalcomponents may be interposed in transmission line path 54B, if desired.

FIG. 7 is a cross-sectional side view of a portion of device 10 in thevicinity of upper region 22. Housing structures 12 may include upperhousing structure 12A (e.g., a display cover layer such as a layer ofcover glass, transparent plastic, or other clear material). Housingstructure 12A may cover display module 14. Gap 82 may separate the edgeof display 14 and peripheral conductive housing structure 16.

Antenna 40 may include an antenna resonating element formed from asegment of peripheral conductive structures 16 and a ground such asground plane 52. Ground plane 52 may include conductive housingstructures (e.g., sheet metal structures), electrical components,conductive traces on printed circuit boards, and other conductivematerials.

As shown in FIG. 7, device 10 may include a printed circuit board suchas printed circuit board 102. Printed circuit board 102 may be used tomount electrical components 122 such as integrated circuits and othercircuits. Conductive traces 104 may form interconnects that interconnectelectrical components 122 with each other. The interconnects in board102 may also form signal paths for antenna signals associated withantenna 40. As shown in FIG. 7, for example, traces 104 on printedcircuit board 102 may be electrically connected to traces 108 on printedcircuit 110 using solder connections such as solder connection 106. Ifdesired, a connector (e.g., a board-to-board connector or other suitableconnector) may be used in connecting traces 104 on printed circuit board102 and traces 108 of printed circuit 110. Welds, conductive adhesive,and other electrical connections may also be used, if desired. The useof solder connections in the configuration of FIG. 7 is merelyillustrative.

Printed circuit board 102 may be, for example, a rigid printed circuitboard such as a printed circuit board formed from fiberglass-filledepoxy (e.g., FR4), a flexible printed circuit, a plastic substrate, asubstrate formed from other suitable dielectrics, or other suitablesubstrate. Traces and components on printed circuit board 102 may formpart of antenna ground 52.

Printed circuit 110 may be a flexible printed circuit (“flex circuit”)formed from a flexible sheet of polymer such as a layer of polyimide orother suitable dielectric substrate. Printed circuit 110 may, as anexample, have a thickness of less than 0.5 mm, less than 0.2 mm, or 0.1mm (as examples). Components 112 may be mounted to printed circuit 110.Components 112 may include radio-frequency filter circuitry, switchingcircuitry, tunable and/or fixed impedance matching circuitry, amplifiercircuitry, transceiver circuitry, and other circuitry. Traces 108 inprinted circuit 110 may be used to interconnect components 112.

Traces 104 and 108 may include conductive structures for formingtransmission line paths (e.g., paths 54A and 54B of FIG. 3). Forexample, traces 104 and 108 may be used to form microstrip transmissionlines or other transmission line structures. Parts of transmission lines54A and 54B may also be formed using other transmission line structures(e.g., segments of coaxial cable transmission lines, segments offlexible printed circuit microstrip transmission line structures orother transmission lines formed from flex circuit substrates).

Printed circuit board 110 may be used to form antenna feed structuresfor the antenna feed for antenna 40 (e.g., feed FA and/or feed FB). Forexample, conductive traces 108 may be used to form an antenna signalpath such as positive antenna feed signal path 58A of FIG. 3 thatbridges gap 82 and may be used in forming ground structures such asground path 56A of FIG. 3. Traces 108 may include surface traces such astraces 120 for coupling traces 108 to peripheral conductive housingstructure 16 via metal screw 114 or other conductive fastener.

Screw 114 may have a head that is used to screw a portion of flexibleprinted circuit 110 into place against inner surface 140 of peripheralconductive housing structures 16. Screw 114 may also have a threadedshaft such as shaft 118 that screws into threads in threaded hole 116 inperipheral conductive housing structure 16. The conductive structures inthe vicinity of screw 114 may form positive antenna feed terminal+ forantenna feed FA. In antenna configurations with multiple feeds,additional screws may form additional positive antenna feed terminals.For example, in a configuration in which antenna 40 has a second antennafeed FB, an additional screw (screw 114′ of FIG. 9) may be used informing positive antenna feed terminal+ for feed FB. Traces 108 may beused in routing antenna signals to the terminals of both feed FA andfeed FB.

If desired, traces 108 may be coupled to peripheral conductive housingstructure 16 using welds, solder, conductive adhesive, fasteners otherthan screws, or other suitable attachment mechanisms. The configurationof FIG. 7 in which conductive traces 108 are coupled to peripheralconductive housing structures 16 using screw 114 is merely illustrative.

Because flexible printed circuit 110 has a substrate formed from a sheetof flexible polymer, flexible printed circuit 110 may be bent to formbend 142. In the vicinity of solder 106, where flexible printed circuit110 is connected to printed circuit 102, flexible printed circuit 110and printed circuit 102 may lie parallel to the X-Y plane. In thevicinity of screw 114, flexible printed circuit 110 may lie in the X-Zplane, perpendicular to the X-Y plane and parallel to inner surface 140of peripheral conductive housing structure 16.

FIG. 8 is a perspective view of housing 12 showing how peripheralconductive housing structure 16 may be formed from segments such assegments 16A, 16B, 16C, and 16D that are separated by gaps 18. Holes 116and 116′ may be used to form threaded openings for screws 114 and 114′for the positive antenna feed terminals of feeds FA and FB,respectively. Segments 16A and 16C may be formed from U-shaped bands ofmetal (e.g., stainless steel, aluminum or other suitable conductivematerial). Segments 16B and 16D may form integral sidewall portions ofplanar rear housing member 12R of housing 12 and may be formed from aconductive material such as metal (e.g., stainless steel, aluminum,etc.). Other types of configurations for housing 12 may be used indevice 10 if desired. The example of FIG. 8 is merely illustrative.

FIG. 9 is a top view of device 10 showing how flexible printed circuit110 or other dielectric substrate (e.g., a rigid printed circuit board,plastic support structure, etc.) may be used in forming antenna feeds FAand FB in upper region 22 of housing 12. As shown in FIG. 9, components122 may be mounted on printed circuit board 102. Components 122 mayinclude control circuitry such as storage and processing circuitry 28 ofFIG. 2 and input-output circuitry 30 of FIG. 2 (e.g., memory chips,processor chips, application-specific integrated circuits,radio-frequency transceiver circuitry, etc.).

Printed circuit board 102 may have an elongated shape with edges thatrun parallel to the longer edges of elongated device housing 12 ofdevice 10 and may have first and second opposing ends 124 and 144.Wireless communications circuitry 34 such as cellular telephonetransceiver circuitry 38, satellite navigation system receiver circuitry35, and additional radio-frequency transceiver circuitry such astransceiver circuitry 36 may be mounted on board 102. For example, oneor more transceiver integrated circuits may be mounted at end 124 ofboard 102.

Transmission lines such as transmission lines 126 and 128 may be used toroute radio-frequency signals between transceiver circuitry in endregion 124 and the antenna feed structures formed from printed circuit110. Transmission lines 126 may include microstrip transmission lines,stripline transmission lines, coaxial cable transmission line,transmission lines formed from thin strips of flexible printed circuitsubstrate (e.g., microstrip transmission lines, stripline transmissionlines, etc.), or other transmission lines. Traces 104 (FIG. 7) may beused to couple transceiver circuitry in region 124 to radio-frequencyconnectors such as connectors 130 and 134. At end 144 of printed circuitboard 102, traces 104 may be coupled between radio-frequency connectors132 and 136 and traces 108 on printed circuit 110 (e.g., via solderconnections 106 formed using hot bar soldering techniques or othersuitable connections).

Transmission line 126 may be coupled between connector 130 and connector132. Transmission line 128 may be coupled between connector 134 andconnector 136. Transmission line 126 may be used to route signalsbetween a first transceiver in region 124 and antenna feed FA.Transmission line 128 may be used to route signals between a secondtransceiver in region 124 and antenna feed FB. Feed FA may have a screwsuch as screw 114 for coupling an antenna signal line formed from traces108 on printed circuit 110 to peripheral conductive housing structure 16and thereby forming a positive antenna feed terminal+ for feed FA. FeedFB may have a screw such as screw 114′ for coupling another antennasignal lines formed from traces 108 on printed circuit 110 to peripheralconductive housing structures 16 and thereby forming a positive antennafeed terminal+ for feed FB. Printed circuit 110 may be sufficientlyflexible to flex along bend axis 146. One or more openings such asopening 148 that overlap with bend axis 146 may be provided in printedcircuit 110 to facilitate bending.

FIG. 10 is a perspective view of flexible printed circuit 110 of FIG. 9,showing how flexible printed circuit 110 may be used to form antennafeed structures for antenna feeds FA and FB in antenna 40. As shown inFIG. 10, flexible printed circuit 110 may have one or more openings suchas opening 148. Opening 148 may be configured to overlap bend axis 146.By removing the polymer material of opening 148 from flexible printedcircuit 110 along axis 146, the flexibility of flexible printed circuit110 may be enhanced. This may help flexible printed circuit 110 bendalong axis 146 to form bend 142.

Solder connections such as solder connection 106 of FIG. 10 may be usedto interconnect the conductive signal paths in printed circuit board 102(e.g., the positive and ground paths such as paths 58A and 56A of path54A and paths 58B and 56B of path 54B of FIG. 3) to corresponding signallines in printed circuit board 110 (e.g., traces 108). The positivesignal line for each feed may extend across gap 82, as shown by lines150 and 152 of FIG. 6. Ground antenna signal traces, positive antennasignal traces, and power supply lines (positive and ground) may also beprovided on flexible printed circuit 110 to couple components 112 toprinted circuit board 102.

A top view of illustrative antenna feed structures of the type that maybe formed using printed circuit board 110 is shown in FIG. 11. As shownin FIG. 11, printed circuit board 110 may have opening such as screwhole openings 160 and 160′. When mounted in device 10, the shaft ofscrew 114 for feed FA may pass through opening 160 until the head ofscrew 114 bears against conductive traces 120 to short conductive traces120 for positive antenna signal line 150 and positive antenna feedterminal+ of feed FA to peripheral conductive housing structure 16. Theshaft of screw 114′ for feed FB may pass through opening 160′ to shortconductive traces 120′ for positive antenna signal line 152 and positiveantenna feed terminal+ of feed FB to peripheral conductive housingstructure 16.

Electrical components 112 may be mounted to flexible printed circuitsubstrate 110 in region 112R. For example, components such as matchingcircuits M1, M2, M3, and/or M4, band pass filter 64A, and low noiseamplifier 86 of FIG. 6 and/or other electrical components may be mountedon flexible printed circuit 110 in region 112R.

By mounting low noise amplifier 86 near end 144 of printed circuit board102 adjacent to feed FA rather than at end 124 of printed circuit board102 near the radio-frequency transceivers at end 124, performance can beenhanced for receiver 35. This is because incoming antenna signals fromfeed FA will be amplified by low noise amplifier 86 before beingsubjected to losses due to the presence of connector 132, transmissionline 126 (e.g., a transmission line having a length of 2-20 cm, morethan 2 cm, about 4-15 cm, less than 10 cm, etc.), and connector 130.Incurring attenuation due to the presence of the signal path (54A)through connector 132, transmission line structure 126, and connector130 only after antenna signals have been amplified by low noiseamplifier 86 can help enhance the signal-to-noise ratio of the receivedsignal that is presented to the input of receiver at end 124 of printedcircuit 144 (e.g., receiver 35).

In general, the antenna feed structure formed from flexible printedcircuit 110 may include any suitable number of low noise amplifiers(LNAs) for amplifying incoming antenna signals. In the configuration ofFIG. 9, feed FA may, for example, be provided with a low noise amplifier(i.e., low noise amplifier 86 of FIG. 6) and associated filter andmatching circuitry (e.g., band pass filter 64A of FIG. 6) that aremounted on printed circuit 110. One or more of the components associatedwith feed FB such as matching networks M2 and M3, filter 64B, antennaselection switch 88, and/or filters 90 may also be mounted on flexibleprinted circuit 110, if desired. Electrical components that are notmounted on printed circuit 110 may be mounted on printed circuit board102 upstream or downstream of transmission line 126 and 128.

Pads P1, P2, P3, P4, P5, and P6 may be coupled to traces in printedcircuit 110 (e.g., traces 108 of FIG. 7) and, via solder connections106, may be coupled to respective traces 104 in printed circuit board102. Traces 108 may include positive and ground antenna signal tracesfor routing radio-frequency signals for feeds FA and FB and traces forrouting positive and ground power supply voltages (e.g., for poweringcircuitry such as low noise amplifier 86, etc.). With one suitablearrangement, pad P1 may be coupled to a trace that forms positiveantenna signal path 152 for feed FB. Pads P2, P3, and P5 may be coupledto ground traces. Pad P4 may be coupled to a trace that forms a positiveantenna signal path. This path may start at conductor 120 of antennafeed FA, may pass through path 150 of FIG. 11, band pass filter 64A, andlow noise amplifier 86, and may terminate at pad P4. Pad P6 may be usedto supply power (e.g., a positive power supply voltage or other suitablepower supply signal) to low noise amplifier 86 and other circuitry onprinted circuit 110.

A cross-sectional side view of device 10 showing how printed circuit 110may be coupled to printed circuit 102 using solder connections 106(e.g., solder connections formed using hot bar soldering techniques) isshown in FIG. 12.

The foregoing is merely illustrative of the principles of this inventionand various modifications can be made by those skilled in the artwithout departing from the scope and spirit of the invention.

What is claimed is:
 1. An electronic device, comprising: conductivehousing structures having a portion that forms at least part of anantenna resonating element of an antenna; a first printed circuit; atleast one electronic component mounted on the printed circuit; a traceon the printed circuit that is coupled to the conductive housingstructures to form an antenna feed terminal for the antenna; and asecond printed circuit coupled to the first printed circuit.
 2. Theelectronic device defined in claim 1 wherein the at least one electroniccomponent comprises a radio-frequency amplifier.
 3. The electronicdevice defined in claim 1 wherein the first printed circuit comprises aflexible printed circuit board and the second printed circuit comprisesa rigid printed circuit board.
 4. The electronic device defined in claim1 wherein the conductive housing structures comprise a peripheralconductive housing structure that runs along at least some of anexternal periphery of the electronic device.
 5. The electronic devicedefined in claim 1 wherein the first printed circuit comprises aflexible printed circuit having a flexible polymer substrate.
 6. Theelectronic device defined in claim 5, further comprising: a solderconnection between the first printed circuit and the flexible printedcircuit.
 7. The electronic device defined in claim 6 further comprisingat least one radio-frequency receiver circuit on the second printedcircuit that is configured to receive antenna signals from the antenna.8. The electronic device defined in claim 7 further comprising: firstand second radio-frequency connectors on the first printed circuit; anda transmission line structure coupled between the first and secondradio-frequency connectors, wherein the radio-frequency receiver circuitis coupled to the first radio-frequency connector, and wherein thesecond radio-frequency connector is coupled to the solder connection. 9.The electronic device defined in claim 1 further comprising a groundstructure for the antenna, wherein the ground structure is separatedfrom the antenna feed terminal by a gap and wherein the first printedcircuit spans the gap.
 10. The electronic device defined in claim 1wherein the antenna has first and second antenna feeds, wherein theantenna feed terminal is associated with the first antenna feed, whereina positive antenna feed terminal is associated with the second antennafeed, wherein the conductive path on the printed circuit that is shortedto the conductive housing structures forms the antenna feed terminal forthe antenna, and wherein an additional conductive path on the printedcircuit is shorted to the conductive housing structures to form thepositive antenna feed terminal.
 11. Apparatus, comprising: an antennahaving a portion that is formed from an electronic device housingstructure; a flexible printed circuit coupled to the electronic devicehousing structure and having a conductive trace that forms at least partof an antenna feed for the antenna; and an electrical component mountedon the flexible printed circuit.
 12. The apparatus defined in claim 11,further comprising: an additional printed circuit coupled to theflexible printed circuit.
 13. The apparatus defined in claim 11, whereinthe conductive trace is coupled to the electrical component mounted onthe flexible printed circuit.
 14. The apparatus defined in claim 11,wherein the electrical component comprises an amplifier.
 15. Theapparatus defined in claim 11, further comprising: ground structuresseparated from the electronic device housing structure by a gap, whereinthe flexible printed circuit has a first portion that extends across thegap from the electronic device housing structure to the groundstructures and a second portion that extends perpendicular to the firstportion from an end of the first portion, and wherein the second portionis electrically connected to the electronic device housing structure bya radio-frequency connector structure.
 16. A printed circuit in anelectronic device, comprising: a conductive trace having a first endthat is coupled to a conductive electronic device housing structure anda second end that is coupled to an additional printed circuit in theelectronic device, wherein the first end forms an antenna feed terminalfor an antenna in the electronic device; an electronic component coupledto the conductive trace; and a flexible printed circuit substrate,wherein the conductive trace is formed on the flexible printed circuitsubstrate.
 17. The printed circuit defined in claim 16, wherein theelectronic component is mounted to the flexible printed circuitsubstrate.
 18. A printed circuit in an electronic device, comprising: aconductive trace having a first end that is coupled to a conductiveelectronic device housing structure and a second end that is coupled toan additional printed circuit in the electronic device, wherein thefirst end forms an antenna feed terminal for an antenna in theelectronic device; and an electronic component coupled to the conductivetrace, wherein the printed circuit has a bend along a bend axis thatruns parallel to an inner surface of the electronic device housingstructure, and the bend axis is formed between the first and second endsof the trace.
 19. The printed circuit defined in claim 18, furthercomprising an opening that overlaps the bend axis.